Electric apparatus



y 2, 1944' L. H. BURNHAM 2,347,989-

AAAAAAAAAAAAAAA US Inventor: Locke H. Burnham, byfiwz 'ss Attcrney.

Patented May 2, 1944 UNITED STATES PATENT OFFICE ELECTRIC APPARATUS Locke H. Burnham, Pittsfield, Mass, assignor to General Electric Company, a corporation of New York 2 Claims.

My invention relates to an electric apparatus, and to an improved integral cooling unit to be attached to the casing of the apparatus.

Heretofore it has been customary in the manufacture of electric induction apparatus such as transformers and reactors to provide an enclosing casing filled with a dielectric fluid such as oil, and allow the oil to circulate through a plurality of groups of tubes which are disposed around the transformer casing. Constructions have also been suggested which include a cooling unit separately mounted on a base and connected to the apparatus casing through which a cooling fluid may be forced such as by providing a pump in the piping connecting the cooler to the casing.

It is therefore an object of my invention to provide an electric apparatus with an improved cooling unit which may be removably and simply attached to the transformer casing.

Another object of my invention is to provide an improved integral cooler construction including a pump attached to the cooler unit which may be simply and removably attached to a casing of an electric induction apparatus.

Further objects and advantages of my invention will become apparent from the following description referring to the accompanying drawing, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification,

In the drawing Fig. 1 is a sectional side elevation of an electric induction apparatus which is provided with an embodiment of my invention; Fig. 2 is a sectional side elevation of an electric induction apparatus provided with a modification of my invention, and Fig. 3 illustrates a modification of the construction illustrated in Fig. 1.

In the drawing I have illustrated an electric induction apparatus including a conventional core surrounded by a plurality of windings l I. The windings are separated so as to provide a duct l2 through which a suitable dielectric and cooling fluid may circulate. The core and coils are enclosed in a suitable casing l3 which is filled with a suitable cooling fluid such as oil to any suitable level such as that indicated by the numeral [4. In order to provide an arrangement for cooling the dielectric fluid I provide a cooler construction l5. This construction may have any suitable shape and includes a box shape having inner and outer sides It and H, a top is and a bottom [9. The transformer tank is provided with openings 20 and 2| near the top and bottom thereof and the cooling unit is provided with similar openings 22 and 23 which are in substantial registery with the openings in the transformer casing. The integral unit l5 may be suitably attached to the side of the casing having the openings 26 and 2| in any suitable manner such as by brazing, welding or bolting at the adjacent surfaces as is indicated by the numeral 24.

In order to force the circulation of the fluid out the top opening and into the unit I provide a pump having an impeller 26. A partition 2'1 is provided adjacent the impeller 28 having an opening 28 to facilitate the forcing of the oil out the opening 2e down through the cooling unit and back into the transformer casing through the opening 25. In order that the cooling fluid may circulate through the duct [2 in the coils instead of between the outer surface of the coils and the casing, a bafiie 36 may be provided. In order to provide supplementary means for cooling the circulating dielectric fluid I provide a suitable coil 3| through which a suitable cooling fluid may circulate, such as water. Any suitable number of coils 3| may be provided and the bottom ends 32 thereof may be attached to a suitable header construction which is provided by a partition 33 which may be welded to the bottom end of the cooling unit IS. A suitable pipe 3 3 may be provided which is connected to the bottom of the side H of the cooler which connects with a chamber 35 which forms a header for the plurality of cooling coils iii. The opposite ends of the cooling coils may extend through apertures 36 in the casing l5 which apertures are surrounded by a box shaped member 31 which is welded to the side ll so as to provide a suitable header construction for the top ends of the cooling coil 3|.

In the arrangement illustrated in Fig. 2 I have shown a similar transformer casing construction 13 having an integral pump and cooler unit 40. The cooler construction includes inner and outer sides 4| and 42 having a bottom 43 and a top 44. A passage 45 at the top connects with a suitable passage 46 at the top of the casing i3 and the bottom of the cooler is provided with a suitable passage 4'5 which connects with an opening 48 in the casing 13. This cooler may be removably attached to the casing I3 in any suitable manner such as by bolting as is indicated by the bolt 49. In order to provide an arrangement for cooling the circulating dielectric fluid a plurality of pipes to are provided in the cooler which are open at the bottom as indicated by the numeral 5|. The tops of the pipes are connected with a header 52 which in turn connects with the atmosphere through an opening 53. In order to provide a single pump construction for pumping both the oil and the air, I provide a pump motor having an oil impeller 56 and an air impeller 51. The oil will be pumped through openings 58 and 53 and by the injection principle will cause oil to also flow through the passage 60. Furthermore the air will be sucked in through the openings 5| of the tube and out through the openings 53 at the top.

In the construction illustrated in Fig. 3 I have provided a box shaped cooler 6| which is suitably attached to a side 52 of the transformer casing. It will be seen that the cooler is provided with an outside surface 63, a top 64 and a bottom 65. Vertical sides of course which are not shown are provided. The unit is then bolted to the side 62 so that the side of the transformer provides an inner side for the cooling unit. Openings 65 and 57 are provided at the top and bottom of the side 62 and a pump 68 is provided which is attached to the top of the cooling unit, the pump having an impeller 69. A baiile it] is provided having an opening H through which a portion of the oil is circulated. It will be noted that the baffle ends close to the outer edge 63 of the cooling unit so as to provide an injection principle for circulation of the oil through the opening 6 and out the opening 61 at the bottom of the cooler. A cooling coil I2 through which any suitable cooling liquid such as 011 may circulate is provided.

Although I have shown and described particular embodiments of my invention, I do not desire to be limited to the particular embodiments described, and I intend in the appended claims to cover all modifications which do not depart from the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electric induction apparatus including an enclosing casing, a dielectric fluid within said casing, a cooling unit, said casing and cooling unit having openings in substantial registery so that said fluid may circulate between said casing and cooling unit, passage means within said cooling unit through which a cooling fluid may pass, partition means integral with the walls of said cooling unit at one end to form a header for said passage means, and pump means mounted on said cooling unit for forcing said fluid from said casing through said unit and back to said casing, said cooling unit and pump means being removable as a unit from said casing.

2. An electric induction apparatus including an enclosing casing, a dielectric fluid within said casing, a cooling unit having one face open, passage means within said cooling unit through which a cooling fluid may pass, means for mounting said cooling unit tightly to a side of said casing so that said side closes said open face of said cooler, said side having spaced openings so that said dielectric fluid may circulate through said cooler and around said passage means, and pump means mounted on said cooling unit for forcing said dielectric fluid from said casing through said unit and back to said casing through said openings.

LOCKE H. BURNHAM. 

